Considering the wide use of encapsulation by modern industry, there is a need to mark capsules with indicia or a pattern for identification or aesthetic purposes. Marking capsules in their final state is difficult and expensive, requiring extra labor and chemicals that may cause adverse effects to consumers. Thus, printing on the gelatin ribbon prior to the encapsulation process is more a cost-effective and accepted practice.
There is known U.S. patent application Ser. No. 10/236,669 for “Method and apparatus for printing a ribbon for packaging gelatin capsules” invented by Cruttenden, Holland, Tidy, and Rowe. This application uses a transfer station to mark the gelatin ribbon prior to encapsulation. The transfer station comprises a print roll (a flexographic printing plate wrapped around a cylinder) that picks up ink off an inking roller immersed in an ink tray. The transfer station is located along the gelatin ribbon's path between the casting drum and the oiling station. The print roll is in contact with the passing gelatin ribbon, driven by a motor at the same speed as the ribbon and depositing indicia or a pattern onto said ribbon. However, this application presents several disadvantages over the present invention. Firstly, it is over twenty times more expensive than the present invention: it requires sensitive and complex components such as a stepper motor, an encoder, prologic controls, speed controllers, air cylinders, and a gear drive assembly. Secondly, this application requires electricity and an air compressor to function. Considering the multitude and inter-dependence of components, this application is more prone to failure and down-time.